(function (){
    //背景类
    var land = window.Land = function (){
        //自己背景
        this.image = game.R.land;

        //图片的位置
        this.x = 0;
        this.y = game.canvas.height * 0.78;
        //png图片的宽度
        this.w = 336;



    }
    //更新
    Land.prototype.update=function (){
        this.x -= 2;
        if(this.x < -this.w){
            this.x = 0;
        }
    }

    //渲染
    Land.prototype.render = function ()
    {
        game.ctx.drawImage(this.image, this.x,this.y);
        game.ctx.drawImage(this.image, this.x + this.w,this.y);
        game.ctx.drawImage(this.image, this.x + this.w * 2,this.y);
        //猫腻的矩形
        game.ctx.fillStyle = "#DED895";
        game.ctx.fillRect(0,this.y + 112,game.canvas.width,game.canvas.height * 0.25 - 112);



    }
})();